Force feed oil filter



July 21, 1936; w. A. MCLEAN 1 2,048,350

FORCE FEED OIL FILTER Filed Febf27, 1953 2 Sheets-Sheet l July 21, 1936.E w, A, MCLEAN I 2,048,350

FORCE FEED OIL FILTER Filed Feb. 27, 1933 2 Sheets-Sheet 2 Patented July21, 1936 UNITED STATES PATENT OFFICE FORCE FEED OIL FILTER ApplicationFebruary 2'], 1933, Serial No. 658,696

2 Claims. (Cl. 210-165) My presentinvention relates to filters and moreparticularly to lubricating oil filters of the type used in thelubricating lines of internal combustion engines to cleanse the oilduring its 5 circulation under pressure from the oil pump,

and it has for its object to provide a simple, compact and eflicientdevice of this character which can be quickly and conveniently takenapartfor cleaning purposes and for the removal and rel newal of thefiltering medium. The improvements are directed in part toward theconstruction of this medium to the end that it may be pre-' pareduniformly in quantities and used as arenewable part to be discarded whenfouled and 15 replaced by afresh unit.

To these and other ends, the invention resides in certain improvementsand ,combinations of parts, all as will be hereinafter more, fullydescribed, the novel features being pointed out in 20 the claims at theend of this specification.

In the drawings:

Fig. 1 is a central vertical section through a filter constructed inaccordance with and illustrating one embodiment of my invention, thefilter unit or cartridge being shown in elevation;

Fig.2 is a similar view of the upper portion of the tank showing themanner in which the filter cartridge is removed by using the securingmeans a for the cover as a handle; 30 Fig. 3 is a top plan view of thecartridge removed;

Fig. 4 is a vertical section taken on the line 4-4 of' Fig. 3, lookingin the direction of the arrows; I

35 Fig. 5 is a broken section taken on the line 5-5 of Fig. 4 looking inthe direction. of the arrows; 1

Fig. 6 is an enlarged fragmentary vertical section through twocontiguous convolutions of 40 the main filtering medium;

Fig. '7 is an enlarged vertical section through a pressure reducingvalve-that I prefer to employ in the inlet connection of the filter, and

Fig. 8 is a. vertical section taken on the line 1*- t of Fig. 7, lookingin the direction of the arrows.

Similar reference numerals throughout the several views indicate thesame parts.

This application discloses a further development of and improvement uponthe general idea embodied in the subject matter of my prior andcopending application, Serial No. 549,963, filed July 10, 1931, and thisbeing the case, the

general, features common to both showings and cation need be onlybriefly described herein. The body of the filter consists, in thepresent instance, of a vertically arranged cylindrical tank a 'I havinga drain plug 2 in its dished bottom.

The rim at the top is flanged at 3 and over it 5 fits a flanged cover 4with the use of an intermediate gasket 5 to tightly seal thetank. Thecover is tightened in place by a bolt 6 extending through a centralaperture therein and having a winged head 1 at the exterior, its innerend 10 being reduced and threaded at 8 for the connection hereinafterdescribed.

The intake oil pipe 9, that usually runs direct from the oil pump, issuitably connected to a side wall of the tank near the bottom todischarge through a suitable reducing valve ID that compensates forpumps of different capacities and causes a uniform volume of flow and amaximum pressure within the tank suitable to the proportions of thefilter. The outlet pipe H is suitably connected. similarly.near the topof the tank. and, of course, delivers to the parts to be lubricated.

Intermediate these two connections, there fits closely within the tank acylindrical unitary'25 filtering medium, the casing of which isindicated at II. This is the removable and replaceable or renewablecartridge" heretofore referred to. In its preferred form, at the presentwriting, it consists of a strip of canton flannel wound into a tightroll I! closely fitting in turn within the casing l2, so that its axisis vertical and its edges are presented to a fiow of oil between theinlets and outlets. Stretchedacross the under face of the roll I3 is ahead ll of muslin or simi- 5 lar textile fabric, while on the top faceis a relatively thick paper or similar fibrous disk IS. The consistencyof this disk is not so light that it might be called flocculent nor isthe pulp, on the other hand, compressed to the firmness 40 of blottingpaper, yet it is of a form-retaining stiffness. It resembles a thickfilter paper. Upon this paper disk I5 is superposed a stiff foraminousmetal disk I6, and the four elements thus assembled, namely, 14, It, It,and it, are held within the casing or shell l2 between beads ll formedby crimping over both upper and lower rims thereof. The said casing i2is preferably made of heavy cartridge paper and the unitary assembly isnot unlike a shotgun shell.

The cartridge need not be supported at the bottom as the pressure of theoil is from below, but its position in this respect, as it is pushedinto the tank, is at least limited by the check valve casing it. Itsupward movement is prevented,

however, beyond a determined position by an expanding split spring ringforming a familiar type of locking abutment l8 that engages the upperbead I! of the cartridge and seats in an annular 5 indentation I! in thewall of the tank. The reduced end 8 of the hand operated bolt 8 threads1 into a central aperture 20 in disk I6 and secures the cover 4 tightlyin place, the cartridge reacting against the lock ring, as aforesaid.Whenit is 1 dwired to replace the cartridge with a fresh one, as happenswhen long use or extremely dirty oil is being treated, the bolt andcover are removed together, the ring I 8 is contracted and removed andthen, as shown in Fig. 2, the bolt is screwed back into the disk l6 andconstitutes a stem or handle, by means of which the cartridge isconveniently withdrawn.

The general functioning of the device as a filter is obvious. As taughtin my copendlng application above referred to. a body of metallic wool2| preferably occupies the bottom of the tank below the inlet 9-'l0,which bodytraps the heavier particles of foreign solid matter in theoil. The latter is thence forced through the musmi drum I4, which bothstrains and acts as a re.-

tainer for confining ravelings on the edges of the roll I3 As shown inFig. 6, the pile l3 on the flannel strip interlaces, as indicated at l3,on contiguous convolutions providing a finer filtering Tmedium, whilethe filter paper 15 above contributes a last efiective cleansing beforethe oil passes out.

The details of the reducing valve III are not pertinent to the abovedescribed invention but, as shown in Figs. 7 and 8, it may-consist of avibratory plunger 22 within the cylinder casing III, which latter has anoutlet 23. I A spring 24 normally holds the plunger from this outlet,while its movement in the opposite direction is limited 40. by a ringnut or threaded inner sleeve 25. After passing through this nut, the oilfinds a tortuous passage around cross threads 26 on one portion of theplunger, eventually passing through a transverse opening 21 to a coreopening 28, shown in dotted lines, and thence to the discharge port 23.

A pressure greater thanthe tank is designed to 6 withstand or isnecessary to the feed forces the plunger ahead against the spring andcloses port 23 until the pressure in the tank is relieved at the outletand the plunger can reach its normal balance again. 10

I claim as my invention:

1. In a force feed oil filter or the like, the combination with a tankhaving a discharge connection and an intake connection, of a detachableand replaceable unitary filtercartridge therefor 11 embodying a casingcontaining a filtering medium, means for securing the cartridge firmlyin the tank between said connections, a cover for the tank, and adetachable device securing the cover to the cartridge, said device beingadapted to be 20 reengaged with the cartridge when the cover is removedto extract the cartridge from the tank.

2. In a force feed oil filter or the like, the combination with a tankhaving a discharge connection and an intake connection, of a detachableand 25 replaceable unitary filter cartridge therefor embodying acontinuous cylindrical casing closely fitting within the tank wallsbetween said connections and containing a strip of fibrous absorbentmaterial wound into a tight roll on the cylin- 30 drical axis and aforaminous disk at one end of the roll, said disk being provided with athreaded opening, means for securing the cartridge firmly in the tankbetween said connections, a cover for the tank, and a detachablethreaded device se- 35 curing the cover to the disk, said device havingan exterior handle and being adapted to be secured back into the diskwhen the cover is removed and detached thereform to extract thecartridge from 0 WILLIAM A. MCLEAN.

the tank.

